Informs 2015

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INFORMS Philadelphia – 2015
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2 - Mixed-integer Programming Formulations for Partial-order Plans
Buser Say, Student, University of Toronto, 5 King’s College Rd.,
ON M5S 3G8, Toronto, ON, M5S 3G8, Canada,
, Andre Augusto Cire, Chris Beck
A partial-order plan (POP) is a set of actions associated with precedence
constraints for which a goal is achieved in any total ordering of actions that
respects the precedence constraints. POPs are more flexible than sequential plans
since agents can dynamically commit to the ordering of certain actions at
execution time. We investigate novel mixed-integer linear formulations to
produce valid POPs from sequential plans, and compare their performance to
state-of-the-art MaxSAT models.
3 - Fast Optimal Chance-constrained Scheduling under Uncertainty
Brian Williams, Professor of Aeronautics and Astronautics, MIT
CSAIL, 32 Vassar St, Cambridge, MA, 02139, United States of
America, Cheng Fang, Andrew Wang
Temporal uncertainty in large-scale logistics requires balancing lost efficiency
through slack and costly replanning when deadlines are missed. This motivates a
computational framework to quantify and bound the risk of violating schedule
requirements. In this work, we decompose the problem into two subproblems: 1)
optimal risk allocation; and 2) enforcing schedule requirements. This allows us to
minimize conservatism while leveraging specialized solvers for each subproblem
for fast solutions.
4 - Linear Optimization for Operator Counting in Automated Planning
Florian Pommerening, University of Basel, Spiegelgasse 5,
Basel, 4051, Switzerland,
Automated planning is the search for paths in factored state spaces. The recently
suggested operator-counting framework uses LP/IP optimization to unify,
combine and explain connections between state-of-the-art planning techniques.
We present an easily accessible introduction to planning and operator counting.
LP/IP methods are a hot topic in planning with significant potential for research
collaborations between OR and AI researchers.
WD27
27-Room 404, Marriott
Optimization Nonlinear Programming I
Contributed Session
Chair: Dongdong Ge, Shanghai University of Finance and Economics,
100 Wudong Road, Shanghai, 200433, China,
1 - An Extended Cutting Plane Approach with PWL Approximation for
Generalized Geometric Programming
Yiduo Zhan, PhD Student, University of Central Florida,
12800 Pegasus Drive, P.O. Box 162993, Orlando, FL, 32816,
United States of America, ,
Chung-Li Tseng, Qipeng Zheng
We employ an extented cutting plane (ECP) approach combining with piecewise-
linear (PWL) approximation to provide the global solution of GGP. In this
approach, the constraints are separated by positive and negative terms. The
negative terms are converted to mixed-integer linear constraints through PWL
approximation. The partially linearized GGP becomes a mixed-integer nonlinear
problem (MINLP). This MINLP is solved using ECP method. Numerical problems
are tested and results are discussed.
2 - Solving Non-separable Quadratic Binary Programs using
Projection and Surrogation
Jaehwan Jeong, Assistant Professor, Radford University,
Department of Management, P.O. Box 6954, Radford, VA, 24142,
United States of America, Chanaka
Edirisinghe
A new approach is developed to solve non-separable quadratic programs with
binary variables. First, separability is induced using a projection technique and
non-convex relaxation of the binary variables. Then, using constraint surrogation,
an iterative sequence of nonconvex separable quadratic knapsack programs are
solved efficiently using our previous algorithms. Preliminary computations are
provided.
3 - Stochastic PDE-constrained Optimization of Vibrations of a Plate
under a Piecewise-linear Current
Dmitry Chernikov, University of Iowa, 1010 W Benton St. #208F,
Iowa City, IA, 52246, United States of America, dmitry-
Pavlo Krokhmal, Olesya Zhupanska
In this work a two-stage stochastic PDE-constrained optimization framework is
applied to the problem of vibration control of a thin composite plate in the
presence of electromagnetic field. The electric current is assumed to be of a
piecewise-linear form. We compute the gradient of the objective function using
adjoint numerical differentiation method. The value of the objective function is
calculated by solving the governing PDEs, and a black-box approach is used for
the minimization problem.
4 - Optimizing Blending Operations at the World’s Largest
Coal Export Port
Fabian Rigterink, The University of Newcastle, Australia,
University Drive, Callaghan NSW, 2308, Australia,
Natashia Boland,
Thomas Kalinowski
The port of Newcastle, Australia, is the world’s largest coal export port. We model
the supply chain’s medium- and long-term planning of blending operations as a
time-expanded pooling problem. Using new multi-commodity flow formulations,
we study the trade-off between continuous and discretized variables (NLP and
MINLP). We evaluate the performance of unary, log unary and binary variable
discretizations in an extensive computational study that concludes the talk.
5 - On the Complexity and Algorithms of Regularized Least
Square Problems
Dongdong Ge, Shanghai University of Finance and Economics,
100 Wudong Road, Shanghai, 200433, China,
, Yinyu Ye, Zizhuo Wang, Hao Yin
We show that finding a global optimal solution for the regularized least square
problem is strong NP-Hard as long as the nonlinear penalty function is concave
and non-decreasing. This result clarifies the complexity for a large class of
regularized optimization problems studied in the recent statistics literature.
WD28
28-Room 405, Marriott
Decision Analysis V
Contributed Session
Chair: Tianqin Shi, San Jose State University, One Washington Square,
Business Tower 450, San Jose, CA, 95192, United States of America,
1 - Group Decision Making: A Flexible Methodology
Pascale Zaraté, Professor, Toulouse 1 Capitole University - IRIT, 2
rue du Doyen Gabriel Marty, Toulouse Cedex 9, 31042, France,
The specific benefice of a collective decision process mainly rests upon the
possibility for the participants to confront their respective points of views. To this
end, they must have cognitive and technical tools that ease the sharing their own
preferences, while allowing keeping some information and feelings for their own.
The paper presents the basis of such a flexible, cooperative decision making
methodology. This methodology has been implemented in a GDSS called GRoUp
Support.
2 - Identifying Patients at Risk using Fuzzy Logic
John Zaleski, Chief Informatics Officer, Nuvon, Inc., 4801 S.
Broad Street, Suite 120, Philadelphia, PA, 19112,
United States of America,
The use of “big data” for decision making has been a growing area of investigation
and usage in healthcare enterprises. This paper shows how fuzzy rules can be
used to operate on data obtained from the point of care to assist in clinical
decision making, with application to real-time data collection in medical surgical
units.
3 - The Effects of Patent Extension and Pharmaceutical Stewardship
Program on Green Pharmacy
Tianqin Shi, San Jose State University, One Washington Square,
Business Tower 450, San Jose, CA, 95192, United States of
America, , Dilip Chhajed, Nicholas Petruzzi
The eco-toxicity arising from unused pharmaceuticals has drawn considerable
attention. In this paper, an innovative pharmaceutical company faces price-
dependent demand and decides whether to adopt green pharmacy in response to
the regulatory policy as well as the competition from a generic company. A
pharmaceutical company incurs a fixed cost to choose green pharmacy. We
examine the impacts of two regulatory policies, patent extension and take-back
regulation, on the choice of green pharmacy.
WD27